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UNITED STATES PATENT OFFICE.

GEORGE FROST. OF BROOKLYN, NEV YORK.

CUT-OFF VALVE FOR STEAM-ENGINES.

Specification of Letters Patent No. 30,138, dated September 25, 1860.

To all whom t may concern:

Be it known that I, GEORGE Fnosr, machinist, of the city of Brooklyn, in the county of Kings and State of New York, have invented a new and useful Improvement in the Manner of Constructing the SlidewValves of Steam-Engines; and I do hereby declare that the following is a full and exact description thereof.

I denominate my invention, improved adjustable governor expansion or cut off valve for slide valves.

In the accompanying` drawings Figure l is a side view of the cylinder forward and after box slide valves, the balance puppet valves, and tripping motion o-f the valves complete. Figs. 2, 3 and 4L, are side views, showing the various positions of the box slide valve, the balance puppet valve, and tripping motion, of the forward valve only. Fig. 5 is a side view of the forward box slide valve, with a reverse motion for opening the balance puppet valve, by means of a lever and showing a small cylinder and piston, having steam continually impinging on its piston, cause the balance puppet valve to close when the catch is disengaged.

In each of these figures, like parts are designated by the same. letters of reference.

S is the cylinder; P, piston; S P, steam ports in the cylinder; E P, exhaust port; E D, exhaust delivery; S O, steam chest; S O, steam pipe; A, box slide valves; B, a plate to connect the forward and after box slide valves together; O, steam ports, in the box slide valves; D, balance puppet valve;

E, balance puppet valve rod; F, adjustable stops; G, arm attached to the balance puppet valve rod; H, small rod to steady the arm; I, catch block, and also as a guide for the balance puppet valve rod; K, catch to retain the balance puppet valve wide open; L, pins on the sliding bars; M, sliding bars; N, rods to connectthe sliding bars with the wheel; O, wheel; R, wheel shaft, part of which is inside and part of it outside of the steam chest; T, a lever fast to the wheel shaft outside of the steam chest; U, rod to connect the wheel shaft lever with the beam; V, beam, the other end of which is shown as broken olf in the drawings, is connected with the governor; X spring, Fig. 5. W, lever; Y, small cylinder and piston; Z, small pipe leading to the exhaust port.

The box slide valve A after completing its backward stroke begins and continues to move forward until the bridge of the valve closes the forward steam port S P of the cylinder and the exhaust port E P begins to open and the steam in the cylinder, S, begins to exhaust at the forward end of the cylinder. Then the balance puppet valve D, in the box slide valve A, begins and continues to openvuntil the exhaust port E P is wide open and is exhausting at the forward end of the cylinder S, as shown by Figs. l and 2.

Fig. 2 shows the box slide valve A after it has completed its forward stroke. The balance puppet valve D is shown wide open by its valve rod E, coming in contact with the adjustable stop F, through the movement of the box slide valve A, admitting steam into it, but not into the cylinder. The catch K now falls down against the catch block I, and retains the balance puppet valve D, in the box slide valve A, wide open until the proper period for tripping it again occurs. The box slide valve A now begins and continues to move backward until the bridge of the valve closes the forward steam port S P of the cylinder. By this time the piston P has completed its forward stroke or the crank has just passed its center, and the iston P is ready to commence its backwar stroke and the box slide valve steam port C, begins and continues to open, admitting steam at the forward end into the cylinder S, as the piston P moves backward.

Fig. 3 shows the steam ports S P, and O, to be half-opened, and steam is passing into the cylinder S. As the box slide valve A moves backward, the catch K now comes in contact with the pins L, on the sliding bars M, which lifts the catch K off the catch block I, and allowing the balance puppet valve D to close. By this time the steam in the cylinder S is cut olf. The box slide valve A still continues to move backward until the steam ports S P' and O are wide open, and has completed its backward stroke, as shown in Fig. t, and the catch K is lifted off the catch block I by the pins L on the sliding bars M, and the balance puppet valve D is closed.

Fig. 5 is a side view of the forward box slide valve A, with a reverse motion for opening the balance puppet valve D by means of a lever W, the fulcrum of which is connected to the top of the box slide valve A, and one end of the lever W is attached to the balance puppet valve rod E, the other cud of it comes in contact with the adjustable stop F, through the movement of the box slide valve A, which adjustable stop F, and the fulcrum of the lever XV can be, as shown in the drawing Fig. 5, above the top or on either side of the boX slide valve A. As the balance puppet valve D, moves parallel with the piston P in horizontal engines, the spring X, or a small cylinder and piston Y, having steam continually impinging on its piston, causes the balance puppet valve D to close, when the catch K is disengaged and prevents any more steam from passing into the cylinder S.

Fig. shows a small pipe Z leading to the exhaust port E P to get rid of any compressed air or steam on the back side of the smallpiston Y. The pins L on the sliding bars M, the bars M being connected by rods N, and wheel O and lever T, to and controlled by the governor, cause the pins L to lift the catch K oil the catch block I, and allowing the balance puppet valve D to .close sooner or later, which constitutes it an adjustable governor expansion or cutoff valve.

Having thus fully described the nature of my improvements in the slide valves of steam engines, what I claim therein as new,

and as my own invention, and desire to secure by Letters Patent is- 1. The opening of the balance puppet valve D, by its valve rod E, coming in contact With the adjustable stop F, through the movement of the box slide valve A.

2. The retaining of the balance puppet valve D' after it is opened, by the catch K, or its equivalent), until the proper period or tripping it again occurs.

3. Tripping the catch K, by the pins L, on the sliding bars M, they being in connection with the governor.

4L. The opening of the balance puppet valve D, the reverse way; by means of a le- Ver l/V, in the manner as described and set forth, through the movement of the boX slide valve A.

5. The closing of the balance puppet valve D, by a small cylinder and piston Y, having steam continually impinging on its piston, when the catch K is disengaged, which cylinder and piston Y, can be arranged in any required position, the Whole being combined, arranged and operating substantially as herein described and set forth.

GERGE FROST.

Witnesses JAMES FROST, JOHN FIRST.

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